Messina is considered as one of the best coaches in Europe of all time. There's not much left for him to win here so it seems natural for him try his luck in NBA.
The person who wants to bring Ettore Messina to Toronto is a vice president and an assitsant general manager Maurizio Gherardini. He is also Italian and worked with Messina in Benetton Treviso.
Gherardini himself is an example of a successful transfer of European basketball experience to NBA. If Messina makes the to Toronto, he would become the first non-American coach in NBA history.